C# IByteSource.GetUInt32方法代码示例

		private void ParseFragmentSequence(IByteSource source, object state) {
			try {
				_result = DicomReaderResult.Processing;

				while (!source.IsEOF) {
					if (_state == ParseState.Tag) {
						source.Mark();

						if (!source.Require(8, ParseFragmentSequence, state)) {
							_result = DicomReaderResult.Suspended;
							return;
						}

						ushort group = source.GetUInt16();
						ushort element = source.GetUInt16();

						DicomTag tag = new DicomTag(group, element);

						if (tag != DicomTag.Item && tag != DicomTag.SequenceDelimitationItem)
							throw new DicomReaderException("Unexpected tag in DICOM fragment sequence: {0}", tag);

						_length = source.GetUInt32();

						if (tag == DicomTag.SequenceDelimitationItem) {
							// end of fragment
							_observer.OnEndFragmentSequence();
							_fragmentItem = 0;
							ResetState();
							ParseDataset(source, PopState());
							return;
						}

						_fragmentItem++;
						_state = ParseState.Value;
					}

					if (_state == ParseState.Value) {
						if (!source.Require(_length, ParseFragmentSequence, state)) {
							_result = DicomReaderResult.Suspended;
							return;
						}

						IByteBuffer buffer = source.GetBuffer(_length);
						if (_fragmentItem == 1)
							buffer = EndianByteBuffer.Create(buffer, source.Endian, 4);
						else
							buffer = EndianByteBuffer.Create(buffer, source.Endian, _vr.UnitSize);
						_observer.OnFragmentSequenceItem(source, buffer);

						_state = ParseState.Tag;
					}
				}
			} catch (Exception e) {
				_exception = e;
				_result = DicomReaderResult.Error;
			} finally {
				if (_result != DicomReaderResult.Processing && _result != DicomReaderResult.Suspended) {
					_async.Set();
				}
			}
		}

		private void ParseDataset(IByteSource source, object state) {
			try {
				_result = DicomReaderResult.Processing;

				while (!source.IsEOF && !source.HasReachedMilestone() && _result == DicomReaderResult.Processing) {
					if (_state == ParseState.Tag) {
						source.Mark();

						if (!source.Require(4, ParseDataset, state)) {
							_result = DicomReaderResult.Suspended;
							return;
						}

						ushort group = source.GetUInt16();
						ushort element = source.GetUInt16();
						DicomPrivateCreator creator = null;

						if (group.IsOdd() && element > 0x00ff) {
							string pvt = null;
							uint card = (uint)(group << 16) + (uint)(element >> 8);
							if (_private.TryGetValue(card, out pvt))
								creator = Dictionary.GetPrivateCreator(pvt);
						}

						_tag = new DicomTag(group, element, creator);

						if (_stop != null && _tag.CompareTo(_stop) >= 0) {
							_result = DicomReaderResult.Stopped;
							return;
						}

						_state = ParseState.VR;
					}

					while (_state == ParseState.VR) {
						if (_tag == DicomTag.Item || _tag == DicomTag.ItemDelimitationItem || _tag == DicomTag.SequenceDelimitationItem) {
							_vr = DicomVR.NONE;
							_state = ParseState.Length;
							break;
						}

						if (IsExplicitVR) {
							if (!source.Require(2, ParseDataset, state)) {
								_result = DicomReaderResult.Suspended;
								return;
							}

							byte[] bytes = source.GetBytes(2);
							string vr = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
							try {
								_vr = DicomVR.Parse(vr);
							} catch {
								// unable to parse VR
								_vr = DicomVR.UN;
							}
						} else {
							DicomDictionaryEntry entry = Dictionary[_tag];
							if (entry != null) {
								if (entry == DicomDictionary.UnknownTag)
									_vr = DicomVR.UN;
								else if (entry.ValueRepresentations.Contains(DicomVR.OB) && entry.ValueRepresentations.Contains(DicomVR.OW))
									_vr = DicomVR.OW; // ???
								else
									_vr = entry.ValueRepresentations.FirstOrDefault();
							}
						}

						if (_vr == null)
							_vr = DicomVR.UN;

						_state = ParseState.Length;

						if (_vr == DicomVR.UN) {
							if (_tag.Element == 0x0000) {
								// Group Length to UL
								_vr = DicomVR.UL;
								break;
							} else if (IsExplicitVR) {
								break;
							}
						}

						if (_tag.IsPrivate) {
							if (_tag.Element != 0x0000 && _tag.Element <= 0x00ff && _vr == DicomVR.UN)
								_vr = DicomVR.LO; // force private creator to LO
						}
					}

					while (_state == ParseState.Length) {
						if (_tag == DicomTag.Item || _tag == DicomTag.ItemDelimitationItem || _tag == DicomTag.SequenceDelimitationItem) {
							if (!source.Require(4, ParseDataset, state)) {
								_result = DicomReaderResult.Suspended;
								return;
							}

							_length = source.GetUInt32();

							_state = ParseState.Value;
							break;
						}
//.........这里部分代码省略.........

		private void ParseItemSequence(IByteSource source, object state) {
			try {
				_result = DicomReaderResult.Processing;

				while (!source.IsEOF && !source.HasReachedMilestone()) {
					if (_state == ParseState.Tag) {
						source.Mark();

						if (!source.Require(8, ParseItemSequence, state)) {
							_result = DicomReaderResult.Suspended;
							return;
						}

						ushort group = source.GetUInt16();
						ushort element = source.GetUInt16();

						_tag = new DicomTag(group, element);

						if (_tag != DicomTag.Item && _tag != DicomTag.SequenceDelimitationItem) {
							// assume invalid sequence
							source.Rewind();
							if (!_implicit)
								source.PopMilestone();
							_observer.OnEndSequence();
							if (_badPrivateSequence) {
								_explicit = !_explicit;
								_badPrivateSequence = false;
							}
							return;
						}

						_length = source.GetUInt32();

						if (_tag == DicomTag.SequenceDelimitationItem) {
							// end of sequence
							_observer.OnEndSequence();
							if (_badPrivateSequence) {
								_explicit = !_explicit;
								_badPrivateSequence = false;
							}
							ResetState();
							return;
						}

						_state = ParseState.Value;
					}

					if (_state == ParseState.Value) {
						if (_length != UndefinedLength) {
							if (!source.Require(_length, ParseItemSequence, state)) {
								_result = DicomReaderResult.Suspended;
								return;
							}

							source.PushMilestone(_length);
						}

						_observer.OnBeginSequenceItem(source, _length);

						ResetState();
						ParseDataset(source, state);
						ResetState();

						_observer.OnEndSequenceItem();
						continue;
					}
				}

				// end of explicit length sequence
				if (source.HasReachedMilestone())
					source.PopMilestone();

				_observer.OnEndSequence();
				if (_badPrivateSequence) {
					_explicit = !_explicit;
					_badPrivateSequence = false;
				}
			} catch (Exception e) {
				_exception = e;
				_result = DicomReaderResult.Error;
			} finally {
				if (_result != DicomReaderResult.Processing && _result != DicomReaderResult.Suspended) {
					_async.Set();
				}
			}
		}

		private bool IsPrivateSequenceBad(IByteSource source) {
			source.Mark();

			try {
				var group = source.GetUInt16();
				var element = source.GetUInt16();
				var tag = new DicomTag(group, element);
				var length = source.GetUInt32();

				group = source.GetUInt16();
				element = source.GetUInt16();
				tag = new DicomTag(group, element);

				byte[] bytes = source.GetBytes(2);
				string vr = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
				try {
					DicomVR.Parse(vr);
					return !_explicit;
				} catch {
					// unable to parse VR
					if (_explicit)
						return true;
				}
			} finally {
				source.Rewind();
			}

			return false;
		}

            private bool ParseFragmentSequenceTag(IByteSource source)
            {
                if (this.parseStage == ParseStage.Tag)
                {
                    source.Mark();

                    if (!source.Require(8))
                    {
                        this.result = DicomReaderResult.Suspended;
                        return false;
                    }

                    var group = source.GetUInt16();
                    var element = source.GetUInt16();

                    DicomTag tag = new DicomTag(@group, element);

                    if (tag != DicomTag.Item && tag != DicomTag.SequenceDelimitationItem)
                    {
                        throw new DicomReaderException("Unexpected tag in DICOM fragment sequence: {0}", tag);
                    }

                    this.length = source.GetUInt32();

                    if (tag == DicomTag.SequenceDelimitationItem)
                    {
                        // end of fragment
                        this.observer.OnEndFragmentSequence();
                        this.fragmentItem = 0;
                        this.ResetState();
                        return false;
                    }

                    this.fragmentItem++;
                    this.parseStage = ParseStage.Value;
                }
                return true;
            }

            private bool ParseItemSequenceTag(IByteSource source)
            {
                if (this.parseStage == ParseStage.Tag)
                {
                    source.Mark();

                    if (!source.Require(8))
                    {
                        this.result = DicomReaderResult.Suspended;
                        return false;
                    }

                    var group = source.GetUInt16();
                    var element = source.GetUInt16();

                    this._tag = new DicomTag(@group, element);

                    if (this._tag != DicomTag.Item && this._tag != DicomTag.SequenceDelimitationItem)
                    {
                        // assume invalid sequence
                        source.Rewind();
                        if (!this._implicit)
                        {
                            source.PopMilestone();
                        }
                        this.observer.OnEndSequence();
                        if (this.badPrivateSequence)
                        {
                            this.isExplicitVR = !this.isExplicitVR;
                            this.badPrivateSequence = false;
                        }
                        return false;
                    }

                    this.length = source.GetUInt32();

                    if (this._tag == DicomTag.SequenceDelimitationItem)
                    {
                        // #64, in case explicit length has been specified despite occurrence of Sequence Delimitation Item
                        if (source.HasReachedMilestone() && source.MilestonesCount > this.sequenceDepth)
                        {
                            this.ResetState();
                            return true;
                        }

                        // end of sequence
                        this.observer.OnEndSequence();
                        if (this.badPrivateSequence)
                        {
                            this.isExplicitVR = !this.isExplicitVR;
                            this.badPrivateSequence = false;
                        }
                        this.ResetState();
                        return false;
                    }

                    this.parseStage = ParseStage.Value;
                }
                return true;
            }

            private bool ParseLength(IByteSource source)
            {
                while (this.parseStage == ParseStage.Length)
                {
                    if (this._tag == DicomTag.Item || this._tag == DicomTag.ItemDelimitationItem
                        || this._tag == DicomTag.SequenceDelimitationItem)
                    {
                        if (!source.Require(4))
                        {
                            this.result = DicomReaderResult.Suspended;
                            return false;
                        }

                        this.length = source.GetUInt32();

                        this.parseStage = ParseStage.Value;
                        break;
                    }

                    if (this.isExplicitVR)
                    {
                        if (this._vr == DicomVR.Implicit)
                        {
                            if (!source.Require(4))
                            {
                                this.result = DicomReaderResult.Suspended;
                                return false;
                            }

                            this.length = source.GetUInt32();

                            // assume that undefined length in implicit VR element is SQ
                            if (this.length == UndefinedLength)
                            {
                                this._vr = DicomVR.SQ;
                            }
                        }
                        else if (this._vr.Is16bitLength)
                        {
                            if (!source.Require(2))
                            {
                                this.result = DicomReaderResult.Suspended;
                                return false;
                            }

                            this.length = source.GetUInt16();
                        }
                        else
                        {
                            if (!source.Require(6))
                            {
                                this.result = DicomReaderResult.Suspended;
                                return false;
                            }

                            source.Skip(2);
                            this.length = source.GetUInt32();

                            // CP-246 (#177) handling
                            // assume that Undefined Length in explicit datasets with VR UN are sequences 
                            // According to CP-246 the sequence shall be handled as ILE, but this will be handled later...
                            // in the current code this needs to be restricted to privates 
                            if (this.length == UndefinedLength && this._vr == DicomVR.UN && this._tag.IsPrivate)
                            {
                                this._vr = DicomVR.SQ;
                            }
                        }
                    }
                    else
                    {
                        if (!source.Require(4))
                        {
                            this.result = DicomReaderResult.Suspended;
                            return false;
                        }

                        this.length = source.GetUInt32();

                        // assume that undefined length in implicit dataset is SQ
                        if (this.length == UndefinedLength && this._vr == DicomVR.UN)
                        {
                            this._vr = DicomVR.SQ;
                        }
                    }

                    this.parseStage = ParseStage.Value;
                }
                return true;
            }

            private static bool IsPrivateSequenceBad(IByteSource source, bool isExplicitVR)
            {
                source.Mark();

                try
                {
                    source.GetUInt16(); // group
                    source.GetUInt16(); // element
                    source.GetUInt32(); // length

                    source.GetUInt16(); // group
                    source.GetUInt16(); // element

                    var bytes = source.GetBytes(2);
                    var vr = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
                    DicomVR dummy;
                    if (DicomVR.TryParse(vr, out dummy)) return !isExplicitVR;
                    // unable to parse VR
                    if (isExplicitVR) return true;
                }
                finally
                {
                    source.Rewind();
                }

                return false;
            }

            private static bool IsPrivateSequenceBad(IByteSource source, bool isExplicitVR)
            {
                source.Mark();

                try
                {
                    // Skip "item" tags; continue skipping until length is non-zero (#223)
                    while (new DicomTag(source.GetUInt16(), source.GetUInt16()) == DicomTag.Item    // group, element
                           & source.GetUInt32() == 0)   // length (using & instead of && enforces RHS to be evaluated regardless of LHS)
                    {
                    }

                    source.GetUInt16(); // group
                    source.GetUInt16(); // element

                    var bytes = source.GetBytes(2);
                    var vr = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
                    DicomVR dummy;
                    if (DicomVR.TryParse(vr, out dummy)) return !isExplicitVR;
                    // unable to parse VR
                    if (isExplicitVR) return true;
                }
                finally
                {
                    source.Rewind();
                }

                return false;
            }